There are certain environments where water is in very limited supply, but yet it is quite desirable for persons living in those environments to be able to cleanse themselves regularly by means of a shower. Such environments include recreational vehicles, boats, and desert locations, for example.
In the United States at the present time, it is somewhat commonplace for a recreational vehicle or a boat to be equipped with a shower. Such showers operate in the same manner as the showers traditionally used in homes and in fine hotels--that is, the water is used once and is expelled away to a drain. In the boat or R.V., however, the person using the shower must generally turn the water on for only a short time interval to wet his body, then after applying soap to his body, may turn the water on for another brief period in order to wash and to remove the soap. This method of showering requires the usage of at least about two or three gallons of water, yet is quite unsatisfactory, particularly if compared to showering in the typical home or hotel shower.
In a typical motor home, for example, there is a separate tank to hold the supply of fresh water, typical capacity being 50 gallons. There are also separate tanks for grey (used) water and for sewage. With the present showering technique in a typical recreational vehicle, as described above, the use of the shower for five days will use up about half of the fresh water supply.